16 October 2018
Slides at ajrominger.github.io/talks

Biodiversity


Biodiversity suports human life

Millennium Assessment Board (2005). Millennium Ecosystem Assessment

Open questions

  • How much biodiversity is required to provision services?
  • How does the current extinction rate compare to background extinction?
  • Are changes to biodiversity largely reversible or irreversible?
  • Is the biodiversity in any given ecosystem in equilibrium or not?
  • How severe is the trade-off between human use of natural resources versus biodiversity?

Biodiversity and ecosystem function

Diversity begets productivity

Reviewed in Duffy (2009) Front. Ecol. Environ.

Biodiversity and ecosystem function

Diversity begets stability

Reviewed in Duffy (2009) Front. Ecol. Environ.

Biodiversity and ecosystem function

Millennium Assessment Board (2005). Millennium Ecosystem Assessment

Biodiversity and ecosystem function

Millennium Assessment Board (2005). Millennium Ecosystem Assessment

Biodiversity and ecosystem function

Are we irreversibly altering biodiversity and ecosystems?

Barnosky et al. (2012). Nature

Biodiversity and ecosystem function

Are we irreversibly altering biodiversity and ecosystems?

40% land conversion globally

Barnosky et al. (2012) Nature; Foley et al. (2005) Nature

Area and isolation

A long precedent for viewing habitat fragments as islands

Diamond et al. (1976) Science

Area and isolation

Equilibrium island biogeography theory

MacArthur & Wilson (1976) The theory of island biogeography

Area and isolation

Equilibrium island biogeography theory

MacArthur & Wilson (1976) The theory of island biogeography

Area and isolation

Equilibrium island biogeography theory

MacArthur & Wilson (1976) The theory of island biogeography

Area and isolation

Human activity: direct conversion

Area and isolation

Human activity: climate change

Area and isolation

Human activity: climate change

Area and isolation…and evolution

Losing evolutionary history

Area and isolation…and evolution

Losing evolutionary history

Area and isolation…and evolution

Losing evolutionary history

Area and isolation…and evolution

Losing evolutionary history

  • Evolution of novel forms takes \(\geq 10^6\) years
  • Intensive agriculture erodes evolutionary history

Karp et al. (2012) Ecology Letters; Frishkoff et al. (2014) Science

Area and isolation…and evolution

Area and isolation…and evolution

Barnosky et al. (2012). Nature

Area and extinction

Species area relationship \(\hat{S} = f(A)\)

Area and extinction

Species extinctions: \(\hat{S}_\text{new} = \hat{S}(A_\text{orig} - A_\text{loss})\)

\(\Rightarrow \hat{S}_\text{extinct} = \hat{S}(A_\text{orig}) - \hat{S}(A_\text{orig} - A_\text{loss})\)

Area and extinction

Species area relationship (classic): \(S = cA^z\)

More nuanced approach: \(S = cA^{z(A)}\)

Harte et al. (2009) Ecology Letters

Area and extinction


  • Assumes:
    • 200 bird species
    • \(S = cA^{0.25}\)
  • Predicts 32 extinctions
  • 4 extinctions observed

Where are all the extinctions?

Where are all the extinctions?

Extinction debt

MacArthur & Wilson (1976) The theory of island biogeography

Where are all the extinctions?

Extinction debt

Reviewed in Kuussaari et al. (2009) TREE

Where are all the extinctions?

Extinction debt

Reviewed in Kuussaari et al. (2009) TREE

Where are all the extinctions?

Extinction debt

Reviewed in Kuussaari et al. (2009) TREE

Where are all the extinctions?

Extinction debt: species interactions





Extinct in 26,600 years

Doughty et al. (2016) Ecography

Where are all the extinctions?

Spatial configuration

Different extinction potential

He and Hubbell (2011) Nature; Keil et al. (2015) Nature Communications

Where are all the extinctions?

Spatial configuration

Different extinction potential

He and Hubbell (2011) Nature; Keil et al. (2015) Nature Communications

Where are all the extinctions?

False dichotomy between social and natural systems

Ecosystems used by humans are not inhospitable "oceans"

Where are all the extinctions?

Especially when human use is diverse

Mendenhall et al. (2014) Nature

Where are all the extinctions?

Especially when human use is diverse

Mendenhall et al. (2014) Nature

Biodiversity and human life

Millennium Assessment Board (2005). Millennium Ecosystem Assessment

Biodiversity and human life

What would a minimum model of human demographics and biodiversity feedbacks look like?

Bibliography and useful readings

Barnosky, A. D., Matzke, N., Tomiya, S., et al. (2011) Has the Earth's sixth mass extinction already arrived? Nature 471: 51.

Barnosky, A. D., Hadly, E. A., Bascompte, J., et al. (2012) Approaching a state shift in Earth's biosphere. Nature 486: 52.

Diamond, J. M., Terborgh, J., Whitcomb, R. F., et al. (1976) Island biogeography and conservation: strategy and limitations. Science 193: 1027.

Doughty, C. E., Wolf, A., Morueta‐Holme, N., et al. (2016). Megafauna extinction, tree species range reduction, and carbon storage in Amazonian forests. Ecography 39: 194.

Frishkoff, L. O., Karp, D. S., M'Gonigle, L. K., et al. (2014) Loss of avian phylogenetic diversity in neotropical agricultural systems. Science 345: 1343.

Harte, J., Smith, A. B., & Storch, D. (2009) Biodiversity scales from plots to biomes with a universal species–area curve. Ecology Letters 12: 789.

Karp, D. S., Rominger, A. J., Zook, J., et al. (2012). Intensive agriculture erodes \(\beta\)‐diversity at large scales. Ecology Letters 15: 963.

Bibliography and useful readings

Keil, P., Storch, D., & Jetz, W. (2015) On the decline of biodiversity due to area loss. Nature Communications 6: 8837.

Kuussaari, M., Bommarco, R., Heikkinen, et al. (2009) Extinction debt: a challenge for biodiversity conservation. Trends in Ecology & Evolution 24: 564.

Losos, J. B., & Schluter, D. (2000) Analysis of an evolutionary species–area relationship. Nature 408: 847.

MacArthur, R. H., & Wilson, E. O. (1976) The theory of island biogeography. Princeton University Press.

Mendenhall, C. D., Karp, D. S., Meyer, C. F., et al. (2014) Predicting biodiversity change and averting collapse in agricultural landscapes. Nature 509: 213.